KR101317038B1 - Waste heat recovery turbine system - Google Patents

Abstract

A turbine 13 driven by the working medium M, an evaporator 16 for vaporizing the working medium M to the turbine 13 by heat exchange with an array from an external heat source, and a turbine 13. And a condenser 17 for liquefying the working medium (M) through (3), and the working medium (M) comprises a compound selected from the group consisting of hydrofluoroether (HFE) and fluorinated alcohol as the main medium.

Description

Waste heat recovery turbine system {WASTE HEAT RECOVERY TURBINE SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste recovery turbine system operating as a working medium having an alternative freon gas having excellent environmental and handling properties as a main medium.

In recent years, a heat recovery turbine system using a heat source such as hot water of less than 100 ° C generated in manufacturing processes in steel mills and ceramics as a heat source uses a low boiling point medium other than water as a working medium. It is attracting attention as a result of saving energy and reducing warming gas. In such turbine systems, chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) as alternative freon gases, which have lower boiling points than natural media such as ammonia, hydrocarbons and water, are used as the working medium. (For example, refer patent document 1).

Japanese Patent Publication 2002-161716

However, among the working mediums, ammonia and hydrocarbons, which are natural mediums, are difficult to handle in view of toxicity and flammability. In addition, chlorofluorocarbons (CFC) and hydrochlorofluorocarbons (HCFC), which are synthetic media, are difficult to use in terms of environmental properties, such as destroying the ozone layer and increasing the global warming coefficient (GWP). Hydrofluorocarbons (HFC) have a zero ozone depletion coefficient (ODP) of zero and do not destroy the ozone layer, but have a slightly higher global warming coefficient. Therefore, in addition to having zero ozone depletion coefficient (ODP) and having a smaller global warming coefficient, an excellent medium in terms of environment is desired.

Therefore, as a result of earnest examination by the inventors, hydrofluorether (HFE) was first discovered. These HFEs are sold by Sumitomos Rem Co., Ltd. under the trade name Novec 7000, and are only used for cleaning semiconductors and electronic components, and have characteristics suitable for these applications. The heat recovery turbine system is a field that is completely different from the manufacture of semiconductors and electronic components, but it has been found that HFE is a suitable medium for the heat recovery turbine system in view of boiling point, latent heat of evaporation, handling and toxicity. Although HFE lacks lubricity, it has also been found that lubricity can be easily provided by mixing lubricant therein. In addition, fluorinated alcohols with characteristics close to HFE in boiling points and latent heat of evaporation have been found to be suitable for heat recovery turbine systems.

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above research, and an object thereof is to provide a heat recovery turbine system which operates as a working medium including an alternative Freon gas having excellent environmental performance and good handling as a main medium.

In order to achieve the above object, the heat recovery turbine system according to the present invention, an evaporator for vaporizing the working medium by the heat exchange between the turbine driven by the working medium and the arrangement from an external heat source to supply the turbine. And a condenser for liquefying the working medium passing through the turbine, wherein the working medium includes a compound selected from the group consisting of hydrofluoroether (HFE) and fluorinated alcohol as the main medium.

According to this configuration, since the compound selected from the group consisting of HFE and 3FE has a low boiling point at ordinary pressure, the working medium including it as a main medium can be easily vaporized by heat exchange with an arrangement from a heat source in an evaporator. have. In addition, since these compounds have a zero ozone depletion coefficient and a low global warming coefficient (GWP), they are environmentally friendly due to their low environmental load, and their handling is good because of their low toxicity.

In the present invention, the main medium is preferably a HFE having a boiling point at normal pressure (hereinafter, simply referred to as a boiling point at normal pressure, referred to as a boiling point at normal pressure) of -24 to 60 ° C. As such, the boiling point of the main medium is -24 to 60 ° C., so that the main medium can be easily vaporized only at a normal arrangement level recovered from the heat source.

In the present invention, it is preferable that the boiling point at normal pressure of HFE as the main medium exceeds 30 ° C. As such, when the boiling point of HFE exceeds 30 ° C., the system can be simplified because the condenser can be easily liquefied with water at room temperature (about 15 to 30 ° C.).

In the present invention, the main medium is preferably HFE having 2 to 4 carbon atoms. When the carbon number of HFE is 2 to 4, since the boiling point at atmospheric pressure is lower than that of water, when the arrangement from the heat source is hot water, the HFE can be easily vaporized by heat exchange with the hot water. As such HFE, for example, C ₃ F ₇ OCH ₃ (HFE7000), C ₄ F ₉ OCH ₃ (HFE7100), C ₄ F ₉ OC ₂ H ₅ (HFE7200), and C ₆ F ₁₃ OCH ₃ (HFE7300 There is). HFE may be CHF ₂ -CF ₂ -O-CH ₂ -CF ₃ (HFE-S7).

In the present invention, the working medium is preferably one in which the main medium is mixed with a lubricating oil compatible with the main medium, for example, fluorine oil. In this way, even if the main medium itself does not have lubricity, the lubricity can be ensured by the lubricating oil mixed in the main medium. In addition, since the lubricating oil made of fluorine oil is compatible with the main medium, it is difficult to separate the main medium and the lubricating oil which are the working medium from the liquid phase of the evaporator, and the working medium having a constant lubricating oil concentration is extracted from any part of the lower part of the evaporator. For example, it can be used for lubrication of the lubrication target part of a turbine.

In the present invention, it is preferable to further include a supply passage for supplying a working medium containing lubricating oil to the bearing. As a result, the lubricating working medium is used for driving the turbine, and is directly supplied to the bearing of the turbine from the supply passage, so that the bearing can be satisfactorily lubricated without a separate supply means for lubricating oil.

In the present invention, there is provided a lubrication system for supplying lubricating oil to the bearing of the turbine, and a sealing portion for sealing between the bearing and the turbine at the outer circumference of the turbine shaft, wherein the lubricating system injects lubricating oil to the bearing. It is preferable to provide a part. In this way, a large amount of lubricating oil can be forcibly injected in the pressurized state to the bearing in a pressurized state, so high-speed rotation is required and effective lubrication and cooling of the bearing are possible even when the heat of the bearing is large. In addition, since the sealing part is sealed between the bearing and the turbine, there is no risk of lubricating oil leaking to the turbine side, so that the lubricating oil can be recovered at a high rate, and the lubricating oil is incorporated into the working medium of the turbine to avoid lowering the thermal efficiency of the turbine. Can be.

In this invention, it is preferable that the bearing of the said turbine is grease lubrication type which grease was enclosed. This eliminates the need for auxiliary equipment such as injection pumps and maintenance as long as grease life is available.

The above objects, other objects, features, and advantages of the present invention will become apparent from the following detailed description of preferred embodiments with reference to the accompanying drawings.

According to the present invention, since the compound selected from the group consisting of HFE and fluorinated alcohol has a low boiling point at ordinary pressure, the working medium including it as a main medium is easily vaporized by heat exchange with an arrangement from a heat source in an evaporator. After passing through the turbine, the liquid is easily liquefied in the condenser. In addition, since these compounds have a zero ozone depletion coefficient and a low global warming coefficient (GWP), they are environmentally friendly due to their low environmental load, and their handling is good because of their low toxicity.

1 is a schematic configuration diagram showing a heat recovery turbine system according to a first embodiment of the present invention.
2 is a characteristic comparison table of a main medium and another medium used in the present invention.
3 is a schematic configuration diagram showing a heat recovery turbine system according to a second embodiment of the present invention.
4 is a longitudinal sectional view showing the injection part in detail.
5 is a schematic configuration diagram showing a heat recovery turbine system according to a third embodiment of the present invention.
FIG. 6 is a longitudinal sectional view showing the bearing of FIG. 5 in detail. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, it demonstrates in detail, referring drawings for preferred embodiment of this invention.

1 shows a schematic configuration diagram of a heat recovery turbine system according to a first embodiment of the present invention. The heat recovery turbine system shown in FIG. 1 includes a turbine power generation unit U having a generator 10 and a turbine 13 for driving the same, and circulates a working medium M for rotationally driving the turbine 13. A falling film type evaporator 16, a condenser 17, and a medium supply pump 18 are provided in the medium passage 30 to be made.

The generator 10 has a generator rotor 11 and a generator stator 12, and turbines 13 and 13 are disposed at both ends thereof, and the generator rotor 11 and the turbine 13, respectively. 13 is connected by a single rotating shaft 21. The rotary shaft 21 is rotatably supported by two bearings 19 and 19 disposed between the generator 10 and the two turbines 13 and 13, and an oil tank is disposed under each of these bearings 19. (V) 25 is provided. The two turbines 13 and 13 are arranged in opposite directions to form a so-called mirror shape, so that the axial thrust acting on both turbines 13 and 13 is canceled to eliminate the thrust bearing. Or simplifying. Therefore, each bearing 19 bears the main radial load of the rotating shaft 21.

The heat source 15 is, for example, an arrangement of hot water or the like generated in a large amount in the manufacturing process of a steel mill or a ceramics industry. The hot water derived from the heat source 15 is introduced into the heat transfer tube 16a in the evaporator 16 through the heating fluid supply passage 15a, and then the heating fluid recovery passage 15b in the heat transfer tube 16a. ) Is returned to the heat source 15 side.

The evaporator 16 vaporizes the working medium M by heat exchange with hot water passing through the heat transfer tube 16a, that is, heat exchange with the arrangement of the heat source 15, and the working medium in the gaseous phase ( M) is supplied to the turbine power generation unit U via the gas phase medium supply path 30a. In the evaporator 16, a circulation pump 27 is provided in a circulation passage 29 arranged to communicate between the lower part and the upper part of the evaporator 16, and the circulation pump 27 is provided at the lower part of the evaporator 16. The taken out liquid working medium (M) is ejected in a shower-like shape into the evaporator 16 through the ejection opening of the injection pipe 26 disposed inside the evaporator 16, and is transferred to the heat transfer tube 16a. Sprinkle to promote heat exchange.

The working medium M after rotationally driving the turbine 13 of the turbine power generation unit U is sent to the condenser 17 via the gas phase medium recovery path 30b. The condenser 17 has a known structure in which a pipe of the cooling medium C is allowed to pass through therein, and the gas condenser 17 is liquefied by cooling the gas phase working medium M with the cooling medium C.

The working medium M liquefied in the condenser 17 is boosted by the medium supply pump 18 provided in the liquid medium supply path 30c when passing through the liquid medium supply path 30c and the evaporator 16. Is supplied. By the liquid medium supply path 30a, the gaseous medium recovery path 30b, and the liquid medium supply path 30c, a medium path 30 which is a circulation path is formed.

An oil tank 25 is provided below each bearing 19. On the other hand, a supply passage 20 branching from the circulation passage 29 is formed at the outlet side of the circulation pump 27, and from the supply passage 20 at the lower portion of the evaporator 16 by the circulation pump 27. A part of the liquid working medium M taken out is supplied to the oil tank 25 under each bearing 19. As shown in FIG. Therefore, the high pressure working medium M is supplied from the oil tank 25 to the bearing 19 so that lubrication is smoothly performed. In addition, the supply passage 20 is provided with a pressure reducer 28 including an aperture or a pressure reducing valve, such as an orifice, to improve the concentration of the lubricating oil by evaporating a part of the liquid working medium M by pressure reduction. In addition, the latent heat of evaporation lowers the temperature of the working medium (M).

Between each bearing 19 and the condenser 17, specifically, between each oil tank 25 and the inlet of the condenser 17, the liquid working medium M discharged from the bearing 19 is transferred to the condenser 17. It is connected by the return passage 23 to return. The liquid working medium M returned to the condenser 17 in the return passage 23 joins the working medium M that has passed through the gaseous medium recovery path 30b in the condenser 17.

As the main medium of the working medium (M), for example, HFE (hydro pulloether ether), that is, in which H of the general formula C _n H _{2n + 1} -O-C _m H _{2m + 1} is partially substituted with F Or a fluorinated alcohol, that is, a part in which H other than OH of C _n H _{2n + 1} -OH is substituted with F.

As the main medium, HFE having 2 to 4 carbon atoms (C) is preferable. When the carbon number of HFE is 2 to 4, since the boiling point at normal pressure is lower than that of water, even if the heat from the heat source 15 is 100 ° C or less, the HFE can be easily vaporized by heat exchange with the hot water.

It is preferable that the said main medium has a boiling point of -24 degreeC-60 degreeC, More preferably, it is more than 30 degreeC and 60 degrees C or less. If the boiling point is 60 ° C. or less, the main medium can be vaporized using a relatively low temperature array recovered from the heat source 15. When it exceeds 30 degreeC, it can be condensed by the water of normal pressure (atmospheric pressure) and normal temperature (about 15-30 degreeC), and can be liquefied easily, and system can be simplified.

Examples of HFE having a boiling point of -24 to 60 ° C include C ₃ F ₇ OCH ₃ (HFE7000) and CHF ₂ -CF ₂ -O-CH ₂ -CF ₃ . As a specific example of C ₃ F ₇ OCH ₃ (HFE7000), there is a trade name Novec 7000 (boiling point 34 ° C.) of Sumitomos LiM Corporation, and as a specific example of CHF ₂ -CF ₂ -O-CH ₂ -CF ₃ , Daikin Kogyo Co., Ltd. brand name HFE-S7 and Asahi Glass's brand name Asahi Clean AE-3000 (as well as a boiling point of 56.7 degreeC, ODP = 0, GWP = 870) are mentioned. CF ₃ OCH ₃ (HFE-143mc, boiling point -24 ° C) with ₂ carbon atoms, CF ₃ CF ₂ OCH ₃ (HFE-245mc, boiling point 5.5 ° C) with 3 carbon atoms, and CHF ₂ CF ₂ OCH ₃ (HFE- 254pc, boiling point 37.2 ° C), CHF ₂ CF ₂ OCH ₂ CF ₃ (HFE-347pc-f, boiling point 56 ° C) with 4 carbon atoms, (CF ₃ ) ₂ CFOCH ₃ (HFE-347mmy, boiling point 29.4 ° C), and CF ₃ CF ₂ CF ₂ OCH ₃ (HFE-347mcc, boiling point 34.2 ° C.).

In addition, even when the boiling point of the main medium exceeds 60 ° C. and the number of carbons (C) is 5 to 7, it can be used when the arrangement temperature from the heat source 15 exceeds the boiling point of the main medium. . Such main media include C ₄ F ₉ OCH ₃ (HFE7100) at a boiling point of 61 ° C., C ₄ F ₉ OC ₂ H ₅ (HFE7200) at 76 ° C., and C ₆ F ₁₃ OCH ₃ (HFE7300) at 98 ° C. .

As the main media, as described above, it may also be a fluorinated alcohol, for example, the formula C _n H _{2n + 1} - is preferred 3FE (3 fluorinated alcohol) by substituting H other than the OH of OH in part F. The 3FE has a boiling point of 74 ° C. at normal pressure, weak flammability, but has an ozone depletion coefficient (ODP) of zero and a low GWP.

As described above, in the present invention, since the ozone depletion coefficient (ODP) is zero (0) and the global warming coefficient (GWP) is also small, the environmental load is low, the environment is excellent, and the toxicity is good. As a result, the evaporator 16 can easily vaporize by heat exchange with the array, and after passing through the turbine 13, can be easily liquefied in the condenser 17.

Here, the reason why the medium represented by the above-mentioned HFE (hydrofluoroether) is applied as the main medium of the heat recovery turbine system will be described with reference to the characteristic comparison table of the medium shown in FIG. In Fig. 2, CFC (chlorofluorocarbon), HCFC (hydrochlorofluorocarbon), HFC (hydrofluorocarbon), HFE and 3FE (trifluorinated alcohol) are illustrated.

As is clear from this characteristic comparison table, all of HFE7000 to 7300 decompose in the atmosphere due to the presence of oxygen (O) in the ether compound, and because the ozone depletion coefficient (ODP) = 0 does not destroy the ozone layer and the global warming coefficient ( GWP) is less than 370, so it is excellent in environment and does not have toxicity. Therefore, as is clear from the comprehensive evaluation, it is excellent as a main medium (◎ mark or ○ mark). Among these, HFE7000 is very excellent in the point which is easy to vaporize because it is 60 degrees C or less of boiling point (the ◎ table). As described above, 3FE has an ozone depletion coefficient (ODP) = 0, a global warming coefficient (GWP) = 57, and excellent environmental performance but weak flammability and requires attention to handling, so the overall evaluation is slightly lower than HFE. ). On the other hand, CFCs and HCFCs are inferior in terms of environmental properties and toxicity (x table). HFCs have relatively good environmental properties but are toxic, so the overall evaluation is lower than that of HFE (△ table).

In addition, although not illustrated in the comparison table, HFO (hydrofluoroolefin) is a medium having excellent environmental properties such as HFE, which can also be used as a main medium. As HFO, for example, HFO-1234yf (Formula CF ₃ CF = CH ₂ ) is mentioned.

By the way, HFE used as the main medium has a low warming coefficient and is an excellent medium which does not destroy the ozone layer, but does not have lubricity. In this embodiment, therefore, the lubricating oil is imparted to the working medium M by mixing lubricating oil made of fluorine oil with HFE.

As lubricating oil mixed in a main medium, the fluorine oil etc. which are represented by the following chemical formula which is the polymerization structure in which the base oil or additive of a lubricating oil partially or all the terminal of a lubricating oil were sealed with fluorine are proposed.

or,

The former includes, for example, the trade name Klytox manufactured by DuPont. This fluorine oil has good compatibility with a main medium such as HFE described above, and the main medium and the fluorine oil are not separated in a liquid state.

The operation of the heat recovery turbine system according to the above configuration will be described with reference to FIG. 1. Hot water drawn as an arrangement from the heat source 15 is introduced into the evaporator 16 in the heating fluid supply passage 15a, and the working medium M in the evaporator 16 is introduced by heat exchange with the introduced hot water, that is, the heat source. It is vaporized by the heat of heat from (15), and it becomes the high pressure gas state of about 4 atmospheres, for example. On the other hand, since the lubricating oil is difficult to evaporate, it remains as the liquid working medium M at a high lubricating oil concentration at the bottom of the evaporator 16.

The working medium M, which has become a gaseous state, is taken out from the upper portion of the evaporator 16 and supplied to the pair of turbines 13 and 13 of the turbine power generation unit U through the gaseous medium supply path 30a. Both turbines 13 and 13 are driven. Thereby, the generator 10 connected by the turbine 13 and the rotating shaft 21 is driven, and electric power generation is performed. The working medium M having released energy from the turbine 13 enters the condenser 17 through the gaseous medium recovery path 30b, and is cooled and condensed by heat exchange with the cooling medium C. In this way, the working medium M, which has become liquid, passes through the liquid medium supply path 30c and is boosted by the medium supply pump 18 to return to the evaporator 16.

Meanwhile, the liquid working medium M having a high lubricating oil concentration remaining in the lower part of the evaporator 16 is supplied to the oil tank 25 of the bearing 19 of the turbine power generation unit U by the supply passage 20. At that time, the working medium M is cooled by the pressure reducer 28 provided in the supply passage 20. In the supply passage 20 in this embodiment, a cooler may be provided instead of the pressure reducer 28 or in addition to the pressure reducer 28. The liquid working medium M supplied to the oil tank 25 from the circulation pump 27 outlet side of the circulation passage 29 is a working medium having a high lubricating oil concentration containing a large amount of lubricating oil. 19) is always well lubricated by the liquid working medium M having a high lubricating oil concentration. Since the bearing 19 can be lubricated by the working medium M having a high lubricating oil concentration, it is not necessary to mix a large amount of lubricating oil with the working medium in order to improve lubricity, so that the front of the evaporator 16 or the condenser 17 can be lubricated. It does not interfere with recession.

It is sufficient that the oil tank 25 has the amount of working medium M necessary for lubrication of the bearing 19, and the surplus is discharged from the oil tank 25 to the return passage 23, and in the return passage 23, the condenser It is returned to (17). Thus, the working medium (M) is discharged out of the system and is circulated and used within the closed system without affecting the environment. The working medium M may be partially in a gaseous state due to the elevated temperature of the bearing 19, and in this case, the working medium M mixed with the liquid phase and the gaseous phase is returned to the condenser 17 through the return passage 23. Enter). Here, since the inlet of the condenser 17 is about atmospheric pressure, the working medium M is smoothly recovered from the oil tank 25 which is slightly high pressure to the condenser 17. In particular, in this embodiment, the circulation pump 27 is operated in a state where the flow rate is constant, unlike the medium supply pump 18 in which the flow rate varies with the liquid level in the evaporator 16. There is an advantage that a stable amount of the liquid working medium (M) having a low lubricating oil concentration can be supplied to the bearing (19) from the supply passage (20) branched from the outlet of the). Further, the downstream end of the return passage 23 may be connected to the medium recovery passage 30b instead of the inlet of the condenser 17.

In this embodiment, the pressure reducer 28 provided in the supply passage 20 causes a part of the working medium M to evaporate, thereby increasing the lubricating oil concentration of the working medium M, and increasing the temperature due to latent heat of evaporation. Since the viscosity of the lubricating oil in the working medium M rises by the fall, favorable lubrication performance is maintained.

As described above, the lubricating working medium M is used for driving the turbine, and is directly supplied to the bearing 19 of the turbine 13 from the supply passage 20 so that the bearing 19 is well lubricated. do.

In the above embodiment, the generator 10 is driven by the turbine 13, but the present invention can be applied to a system in which the turbine 13 drives other loads such as pumps of plants. .

3 shows a heat recovery turbine system according to a second embodiment of the present invention. In this second embodiment, the same parts as those in the first embodiment shown in Fig. 1 are given the same reference numerals and the detailed description thereof will be omitted. In the first embodiment, as shown in Fig. 1, the supply passage 20 for supplying the working medium M into which the lubricating oil L is mixed is supplied to the bearing 19 of the turbine 13. In contrast, in the second embodiment of FIG. 3, the lubricating oil L is stored in the bearing 19 of the turbine 13 in place of the supply passage 20 by using the working medium M without lubricating oil. The lubrication system 40 is newly installed. The lubrication system 40 is provided between a lubricating oil storage tank 41 for storing the lubricating oil L, and an injection part 33 for injecting lubricating oil L into the lubricating oil storage tank 41 and the bearings 19 and 19. The lubricating oil supply passage 42 to be connected and the injection pump 43 which pressurizes the lubricating oil L and send it to the injection part 33 are provided. The lubricating oil L injected from the injection part 33 to the bearings 19 and 19 is returned to the lubricating oil storage tank 41 by the return passage 35, and is used repeatedly.

4 shows the details of the injection part 33. As shown in FIG. 4, an inner ring spacer 36 fixed to the rotating shaft 21 and an outer ring spacer 37 fixed to the housing H are disposed between the left and right pairs of bearings 19 and 19. The injection nozzle 38 is provided in the outer ring spacer 37. The injection nozzle 38 has an inlet 38a at the center and an injection passage 38b branched from the inlet 38a toward the left and right bearings 19 and 19, and the tip of the injection passage 38b is The bearing space 19c between the inner ring 19a and the outer ring 19b of the bearing 19 faces the bearing space 19c, and lubricating oil L is sprayed on the rolling element 19d through the bearing space 19c. In the housing H, the downstream part of the lubricating oil supply passage 42 which supplies the lubricating oil L to the injection part 33, and the upstream part of the return passage 35 of the lubricating oil L are formed. One to two injection nozzles 38 are provided for each of the bearings 19 and 19.

Between the bearing 19 and the turbine 13 outer periphery of the rotating shaft 14 of the turbine 13, the sealing part 39 which seals between both 19 and 13 is provided, and the generator 10 (FIG. 3) The sealing part 39 is provided also between the bearing 19 of the rotor 11 outer periphery of the rotor 11, and the generator 10. The sealing part 39 is comprised by the sealing ring fixed to the housing | casing H, and forming a labyrinth seal between the outer peripheral surface of the rotating shaft 14, and a sealing ring.

In the second embodiment, as shown in FIG. 3, the lubricant L from the lubricant storage tank 41 passes through the lubricant oil supply passage 42 and is injected by the jetting portion 33 by high-speed injection so that the bearing ( 19, 19) is lubricated. Therefore, even when high speed rotation is required and the heat generation of the bearing is large, the bearing 19 can be effectively lubricated and cooled. In addition, since the sealing parts 39 and 39 are provided on both sides of the bearing 19, the lubricant L used for lubrication of the bearing 19 is unlikely to leak to the turbine 13 side and the rotor 11 side. Lubricant L can be recovered at a ratio. In addition, the lubricating oil L may be prevented from being mixed in the working medium M of the turbine 13 to lower the thermal efficiency of the turbine 13.

5 shows a heat recovery turbine system according to a third embodiment of the present invention. In this third embodiment, a grease lubricated bearing 19B in which grease G is sealed in place of the bearing 19 of the turbine 13 is used.

6 shows the details of the bearing 19B. As shown in Fig. 6, this bearing 19B is supported between the bearing outer ring 19Ba and the bearing inner ring 19Bb by rolling the support body 19Bd by the support 19Bc so as to enable rolling motion. A pair of sealing plates 19Be and 19Be are provided in the axial outer side of 19Bc). The upper end of the sealing plate 19Be is engaged with the groove provided in the inner circumferential surface of the bearing outer ring 19Ba, and the lower end of the sealing plate 19Be is rotated by the bearing inner ring 19Bb which rotates integrally with the rotation shaft 21. It is close to the outer circumferential surface of the bearing inner ring 19Bb with a slight gap h such that there is no problem. Gel-type grease G is enclosed in a bearing space surrounded by the bearing outer ring 19Ba, the bearing inner ring 19Bb and the pair of sealing plates 19Be and 19Be, so that the rolling element 19Bd is always grease ( It is immersed in G). The grease (G) has a constant viscosity and there is no risk of leaking from the gap (h) to the outside due to its surface tension, and the bearing (19B) is always as long as there is a lifetime such as lubrication characteristics of the grease (G). It is lubricated stably.

As in the second embodiment shown in Fig. 4, two bearings 19B may be side by side. In addition, similarly to the second embodiment, a sealing portion for sealing the bearing 19B of FIG. 5 and the turbine 13 and the generator 10 is provided so that the grease G is installed on the turbine 13 side or the generator 10. You may not leak to the side.

In the case of this third embodiment, auxiliary equipment such as the supply passage 20 used in the first embodiment or the lubricating oil supply passage 42 and the injection pump 43 used in the second embodiment becomes unnecessary, thereby simplifying the structure. Maintenance and maintenance are unnecessary as long as the grease life is maintained.

As mentioned above, although the preferred embodiment was described referring drawings, those skilled in the art will easily assume various changes and corrections within the obvious range by looking at this specification. Accordingly, such changes and modifications are to be interpreted as falling within the scope of the present invention as defined by the appended claims.

C: cooling medium
G: Grease
M: working medium
L: Lubricant
U: Turbine Power Generation Unit
10: generator
13: turbine
15: heat source
16: Evaporator
16a: heat pipe
17: condenser
18: Medium supply pump
19: bearing
19B: Grease Sealed Bearing
20: supply passage
26: injection pipe
27: circulation pump
28: pressure reducer
29: circulation passage
30: media passage
30a: Meteorological Carriers
30b: weather media recovery furnace
30c: liquid media feeder
35: return path
39: sealing part
40: lubrication system
41: lubricant reservoir
42: lubricant supply passage
43: injection pump

Claims (11)

A turbine driven by a working medium,
An evaporator for vaporizing and supplying the working medium to the turbine by heat exchange with an arrangement from an external heat source, and a condenser for liquefying the working medium passing through the turbine,
And the working medium comprises, as a main medium, hydrofluoroether (HFE) having a boiling point of -24 to 60 ° C.
The heat recovery turbine system according to claim 1, wherein the main medium is HFE having 2 to 4 carbon atoms.
The heat recovery turbine system according to claim 2, wherein the HFE is CHF ₂ -CF ₂ -O-CH ₂ -CF ₃ .
The heat recovery turbine system according to claim 1, wherein a boiling point at atmospheric pressure of the HFE, which is the main medium, exceeds 30 ° C.
The heat recovery turbine system according to claim 1, wherein the HFE is C ₃ F ₇ OCH ₃ .
The heat recovery turbine system according to any one of claims 1 to 5, wherein the working medium is a mixture of lubricating oil compatible with the main medium.
The heat recovery turbine system according to claim 6, wherein the lubricating oil is fluorine oil.
The heat recovery turbine system according to claim 6, further comprising a supply passage for supplying the working medium to the bearing of the turbine.
The lubrication system according to any one of claims 1 to 5, further comprising a lubrication system for supplying lubricating oil to the bearings of the turbine, and a sealing portion for sealing between the bearing and the turbine at the outer circumference of the turbine shaft. An array recovery turbine system, comprising: an injection unit for injecting lubricant into the bearing.
The heat recovery turbine system according to any one of claims 1 to 5, wherein the bearing of the turbine is grease lubricated with grease.
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